Flexible element



J. K. wooD FLEXIBLE min/mmv oct. 11 192.7.

Filed Nov. 8, 1924 y( 5 `ATTORNEY Patented Oct. 11, 1927.

msnen KAYE Woon, or NEW'YORK, N. Y., AssIGNoR 'ro WESTINGHO'SE ELECTRC e MaNUnAeLUnrNG COMPANY. 'AconPonATron `or PENNSYLVANIA.

FLEXIBLE` ELEMENT.

Application filed November S, 1 924. Serial No. 748,553.` I

My invention relates to flexible elements. more particularly to flexible gear elements in which it is desired to provide a.v ,resilient connection between the outer Working rim or toothed periphery and the centerhub portion by means of which it is mounted.y

lt is among the objects of my invention to provide a flexible gear element which shall be of simple, compact mechanicalconstrue tion comprising a minimum of parts.

Another object of my invention is to provide a flexible gear Wheel in which the flexible; element shall constitute an integral part of the vWheel member.

`Another object ofmy invention is to provide a flexible gear elementvof the above designated character in which the flexible efement shall be so designedas to give a load'- dellection curve Characteristic of a highly desirable type.

Still another object of my invention is to provide a flexible element having a spring with a characteristic curve which shall eli'ectively eliminate sustainedoscillations.

Various types of gear elements embodying flexible or resilient means have been heretofore proposed which embody l.different types of flexible elements such -as coil springs, spring nests, radial springs and other types and these structures are generally of a very complex nature comprising a plurality of parts which complicates to a great extent the manufacture, assembly and `renewal of the Vgear Wheel members. However, sincel tlexi ble gear Wheels are essential for someappications Where it is necessary to absorb or diminish the effect of shocks and impacts transmitted through the gears to the delicate part of a drive mechanism orlmachine, these Ytypes of gear Wheels have been in common use notwithstanding their many disadvantages.

My present invention is directed to` a flexile gear element which eliminates the use of multiple spring units thereby obviating the di'tliculties' heretofore encountered and although my invention is susceptible of various modifications and designs which permit the application of this type of gear Wheelto a variety of uses, it is especially kapplicable for heavy duty service.

In practicing my invention, I utilize a gear Wheel of solid construction having expanded rim and hub portions With a Web portion of lesser cross section, although this relation is not material. I provideua plurality. of, slotted openings in the Web portion thereof in any suitable manner to provide a flexible connection between the hub `and therim portions, and furthermore, I may form the openings in such Amanner that the remaining sectionWill function to limit the maximum stress of the material for leither direction of rotation. i I

In theaccompanying drawing constituting a part hereof and in which like reference characters designate like parts.: n i

Figure l is an elevationall veW1of a gear Wheel with the side plates removed and eurbodying the principles of my invention,

Fig. 2 is a cross-sectional vievvA thereof taken along then linesII-ll of Fig. l, and

Fig. 3 is a load vdeflection diagram showing the spring characteristic Vof the gear Wheel under load;

Referring,toFigs l and 2, the structure therein illustrated comprises integral hub, web and rim sections 1,2 and 3, respectively,l of a gear Wheel havingits outer periphery .provided with gear teeth 4 and the hub inemberV provided with a central opening 5 for mounting the same on an axle orshaft. The web portion 2 is provided With slottedopenings Gformed in the manner shovvn in, Fig. 1, in any suitable manner as by a jig-saw, cutting torch, or electric arc. The Width of `the opening 6 may be in any proportion to the metal portion, although the minimum Width, which may be determined by'practical methods, is most desirable since such a design Will more `readily give the characteristie shownrbythe curve in ig. 8.

As shown in Fig. l, the web portion is so slotted as to provide a centralY or main coil member 7 Which constitutes substantially a ring member in the center' of the web, centrally of which areformed a pair of cantilevers 8 of relatively` short length and of arcuate shapes. Externally of the coil meinber 7 I provideanother pair of cantilevers 9 of a similar shape but preferably ofsuch size as to give springy action equivalent to that ofthe central cantilevers 8.

I`v further provide a plurality of screw boltsflOvvhich are disposed inthe slot 6v on the inner and the' router sides ofV the cantiylevers-'8.and 9 'respectively as'shovvn inFig.

1. The object of the screvvv bolts is to shorten or lengthen the cantilevers in accordance with the loaol it is desired to transmit.

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Referring to Fig. 2, the rim member 3 is provided'with radial recesses 11 which are adapted to receive a pair of disks 12 that are placed in, or shrunk on, vthe rim of the gear. Clearance is provided between the disk and the extensions 13 of the hub portion 1 to permit of relative movement of thehub and rim 1 and 3 respectively. The disks 12 function to maintain the gear wheel con centric at all times and also to prevent grit and other foreign-substances from entering the web portion which may be lubricated. The bolts 10 are contained within the cover plates 12 so that the gear wheel has an appearance of a usual gear with straight sided faces on its webbed portion. The plates 12 should be of sufficient thickness to give ample strength. The rubbing or friction between the plates 12 and extensions 13 is desirable since it'aids in the dampening of the spring oscillations.

The operation of this device is `briefly as follows: Assuming that the gear wheel, Fig. 1 isrotating in a clockwise direction and torque is being transmitted from the rim to the hub or vice versa through the web portion 2, the function of the flexible web portion will be such that the main coil spring 7 presses th-e cantilevers 8 at their lower extremities thus giving a normal component for the desirable amount of friction. For the opposite direction of rotation, a similar action occurs at the lower extremity of the cantilevers 9. This action is illustrated in the deflection diagram, Fig. 3, and begins at the line 0. With increase of deflection beyond 0 the area of contact between the cantilevers and the main coil spring increases which results in an increasing normal component thereby giving the charac teristic shown in Fig. 3. rIhe proper resiliency or spring characteristic of the gear to be used may be obtained by adjusting the screw bolts 10. j

It is evident from the above description of my invention that flexible gear elements made in accordance therewith provide simple and durable means for absorbing shock and impact in a running train of gear wheels. The design of the flexible element is such as to provide a large range of resilience and to obtain a desirable amount of friction which renders this type of gear element particularly adapted for jack-shaft gears of electrically propelled railway vehicles. In this type of drive it is necessary7 to obtain a strong, durable, flexible element which is capable of producing a uniform load distribution on the teeth of a pair of gear wheels coupled at the opposite ends of the jack-shaft. It is also essentialto provide a yielding characteristic necessary to absorb the shock or impact resulting from the pounding of the connecting rods or the wheels on the rails to protect the more delicate parts such as they windings of the driving motors. Y

Although I have described a specific ein bodimentof my invention, it will be obvious to those skilled in the art, that various changes may be made in the details of construction such as in the proportion and the d-esign of the several co-operating parts without departing from the principles herein set forth.

I claim as my invention:

l. A flexible element comprising a unitaryy disk-shape member having a cut-out web portion, a part of which constitutes a spring element, and adjustable means for varying certain characteristics of said spring element.

2. A flexible element comprising a unitary disk-shape member having a cutout web portion, a part of whichconstitutes a spring element, means for varying the characteristics of said spring element and means for providing a suitable friction component.

A flexible element comprising a wheel member having expanded vrim and hub portions and a cut-out web portion, said web portion constituting a plurality of pairs ef' cantilever springs. and adjustable means for varying the characteristics of said springs.

4. A flexible element comprising a wheel member having expanded rim and hub portions and acut-Out web portion, said web portion constituting a plurality of `coil and cantilever springs.

5. A flexible elem-ent comprising a wheel member having expanded rim and hub portions and a cut-outweb portion. said web portion constituting al plurality of coil and cantilever springs and means for varying the effective length of said cantilevers.

6. A flexible element comprising` a wheel member having expanded rim and hub portions and a cut-out web portion, said web port-ion constituting a coil spring having a plurality of cantilever springs disposed internally and externally thereof.

7. A flexible element comprising a whe-el member having expanded rim and hub portions and a cut-out web portion, said web portion constituting a coil spring having a plurality7 of curved cantilever springs disposed internally and externally thereof, means for adjusting the 4effective length of said cantilevers to provide a desired friction component for either direction of rotation.

In testimony whereof, I have hereunto subscribed my name this 29th day of October, 1924.

JOSEPH KAYE WooD. 

